Methine dyestuffs



Patented Oct. 24, 1950 METHINE DYESTUFFS John David Kendall and GeorgeFrank Dnflin,

Ilford, England, assignors to Ilford Limited Ilford, England, a Britishcompany No Drawing. Application November 9, 1948, Serial N 0. 59,181. InGreat Britain Nov. 10, 1947 18 Claims.

This invention relates to the manufacture of dyestuffs and particularlyto the manufacture of methine dyestuffs containing a thiazolidone ring.

In our co-pending application Serial No. 59,180, filed on even dateherewith and corresponding to British application No. 29,921/47, we havedescribedthe production of, compounds of the general formula I:

where D is the residue of a five-membered or six-membered heterocyclicnitrogen nucleus. Thus D may be a chain of 2 or 3 atoms selected fromcarbon and nitrogen, at least one of these atoms being carbon. Thesecompounds are prepared by heating a compound -of the general formula II:7

[,NH 1% cnsomooon N II methine dyestuffs are obtained by reacting acompound of the general formula I with (as second reactant) an alkyl oraralkyl quaternary salt of a heterocyclic nitrogen compound of any ofthe types well known and described for use in the production of cyaninedyes, which contains a reactive thioether or selenoether group (whichexpression includes an aryl-, alkylor aralkyl-,

thioether or -selenoether group and groups of any of these types whichare separated from the heterocyclic nitrogen nucleus by two or moremethine or substituted methine' groups), or an aminovinyl type ofgroup,i. e. a

group where n is a positive integer or an N- substituted group of thistype (including N-aryl, N acyl and N-acyl-aryl groups of this type).

The various reactions are based on the reactivity of the methylene groupof the thiazolidone ring of the compound of general formula I and dependon the removal of the two hydrogen atoms of that group with theresulting formation of a double bond linking the carbon atom of themethylene group to the residue of the other reactant. I

Thus dyestuffs of particular value which may be produced by the processof the present invention conform to the general formula:

where D has the significance given above, D1 is the residue of aheterocyclic nitrogen compound of the type commonly used in cyaninedyes, n is selected from the class consisting of nought, 1, 2 and 3, andm is selected from the class consisting of nought and one.

The residue D may be, for example, the residue of an iminazole,dihydroiminazole, benziminazole, pyrimidine, quinazoline, triazole andtheir keto derivatives, e. g. pyrimidone, iminazolone or triazolone.

Heterocyclic nitrogen compounds with which the compounds of generalformula I may be reacted are, for example, the alkyl or aralkylquaternary salts of thiazoles, thiazolines, ox-

azoles, 'oxazolines, selenazoles; selenazolines, pyridines, quinolines,lepidines, indolenines, diazines (for example pyrimidines), thiodiazolesand quinazolines, and the corresponding substituted and unsubstitutedpolycyclic compounds of these series such as benzthiazoles,naphthathiazoles and anthrathiazoles, and also the diazoles described inBritish Patent No. 425,609.

These compounds may contain in a or v position to the heterocyclicquaternary nitrogen atom any of the following groupings:

where n is a small integer, e. g. 1, 2 or 3, R1 is 3 an alkyl, aryl, oraralkyl group, R2 and Rs are each a hydrogen atom or a hydrocarbongroup, and R4 and R5 are aryl or acyl groups.

The quaternary salt may be, for example, an alkyl or aralkyl sulphate,halide (e. g. chloride, bromide or iodide), p-toluene sulphonate orperchlorate.

Where in this specification alkyl groups are referred to they may be,for example, methyl, ethyl, propyl, butyl or higher alkyl groups; arylgroups may be, for example, phenyl or naphthyl, and aralkyl groups maybe, for example, benzyl and naphthylmethyl. The term acyl group isintended to mean a group of the structure R.CO where R is a hydrocarbongroup.

It is not essential according to this invention to isolate the compoundof general formula I from the reaction mixture in which it is formed,and indeed it is a very convenient process according to this inventionto form the compound of general formula I and the methine dyestuff fromit as a single operation. This is effected by reacting together acompound of general formula II, a dehydrating solvent such as aceticanhydride or propionic anhydride, and the heterocyclic nitrogen compoundreferred toas the second reactant:

' Preferably,-in cases where the second reactant is a heterocyclicnitrogen compound containing a '-reactive group as specified above, thereaction is effected in the presence of an acid binding agent, e. g.sodium acetate or an organic base such-as pyridine or triethylamine.'Where the reaction mixturealso contains anacid anhydride it ispreferred to use a tertiary organic base.

The dyestuffs obtained according to this invention are' in generalvaluable sensitisers for silver halide photographic emulsions.

The following examples, in which all the parts are by weight, serve toillustrate the invention.

Example. 1 w 7 Preparationv of: the .dyestufi of the formula:

"0.475 part of 2:3-(benziminazo-1'z2f)ethiazol-idone,- 4 and 0.98;partof 2 w-ethylthio vinyl benzoxazole methyl p-toluene sulphonate weredissolved in 20 parts of .alcohol' and 0.4 part of N aana/ t 0475 partof 2:3-(benziminazo-l:2'-)thiazolidone-4 and 1.125 parts of2-w-acetanilido 4 vinyl benzthiazole ethiodide were dissolved in 20parts of alcohol. 0.4 part of triethylamine was added and the solutionboiled for 20 minutes on the water-bath. It was cooled, filtered and thecrude dye boiled out twice with 200 parts of methanol. M. Pt. 284 C.

This dye, when incorporated in a gelatino silver iodobromide emulsion,imparted a band of sensitivity extending to 5900 A. with a shallowmaximum at about 5200 A.

Example} Preparation of the dyestuff of the formula:

0.475 part of 2:13,-(benz minazo 1':2?)-thiazolidone-4 and 1.12,;partsjof 2 wgacetanilido vinyl 3 ;13 dimethyl indolenine methiodide weredissolved in 25 parts of ethyl alcohol and 0.5 part of.

triethylamine added. The solution was boiled on a water-bath for 20minutes, poured into water and filtered. The crude dye was boiled outtwice with parts of methanol. M.'Pt. 246 C.

1.00 part of S EG -keto 4-methyl dihydro- Dyrimidyl-(2)'l*thioglycollic.acid and 2.24 parts of -'2=w,- ace,tanilido-vinyl3': 3-dimethylindolenine.

methiodide were dissolved in 20 parts of pyridine,

1.0 part of acetic anhydric was added and the,

mixture heated on the water-bath. for one hour. It was poured intowater, cooled and allowed to crystallise and filtered. The crude dye wasboiled outwith 200 parts of methanol. M- Pt. 236 C. ,ExampleGPreparation of the dyestuif of the formulae:

CHaO-N (i it S H -s V l o=o O--N-O6 go-ILL (i113 1.00 part of S-[6-ketoll-methyl dihydropyrimidy1-(2)l thiogylcollic acid and 1.62 parts ofZ-methylthio benzthiazole methiodide were dissolved in 20 parts ofpyridine and 1 part of acetic anhydride added. The mixture was heated onthe water-bath for 30 minutes, cooled, diluted with an equal volume ofalcohol and filtered. The crude dye was boiled out with 200 parts ofmethanol. M. Pt. 300 C.

Example 7 Preparation of the dyestuff of the formulae:

N g JHa 1.18 parts of S[4-keto dihydroquinazolyl-(Z) thioglycollic acidand 2.24 parts of 2-w-acetanilido vinyl 3:3-dimethylindoleninemethiodide were dissolved in 20 parts of pyridine, 1.0 part of aceticanhydride was added and the mixture heated on the water-bath for onehour. It was poured into water, cooled, and crystallised and filtered.The crude dye was boiled out twice with 100 parts of methanol. M. Pt.281 C.

, Example 8 Prep'aration of the dyestufi of the formulae:

, s V oo o=ro j \N I 1.18 parts of SE4-keto dihydroquinazolyl-(2)lthioglycollic acid and 1.62 parts of 2-methylthio benzthiazolemethiodide were dissolved in parts of pyridine and 1 part of aceticanhydride added. The mixture was heated on the water-bath for minutes,cooled, diluted with an equal volume of ethyl alcohol and filtered. Thecrude dye was boiled out twice with 200 parts of methanol. M. Pt. 300 C.

Example 9 Preparation of the dyestufi of the formula:

cg. cm

COC=CHOH=C 5-methyl 1:3:4-triazole 2-thioglycollic acid (0.5 part byweight) and 2-w-acetanilid0viny1 3:3- dimethyl indolenine methiodide(1.29 parts by weight) were dissolved in pyridine (10 parts by volume)and acetic anhydride (1 part by volume) was added. The mixture wasboiled for one hour, poured into water and the precipitated dye filteredofi. 'It wasboiled out with methyl alcohol parts by volume) yielding theproduct as an orange powder, M. Pt. above 300-.

What we claim is:

1. Process for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

where D is a chain of more than one and less than 4 atoms selected fromcarbon and nitrogen, at least one oi these atoms being carbon, with analkyl or aralkyl quaternary, salt of a heterocyclic nitrogen compound ofany of the types well known and described for use in the production fcyanine dyes which contain in one of the on and 7 positions to thequaternarynitrogen atom a reactive group selected from the classconsisting of thioether, selenoether and'aminovinyl groups.

3. Process-for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

C O-GHi whereD is the residue. of apyrimidyl nucleus with an alkyl oraralkyl quaternary salt of a heterocyclic nitrogen compound of any ofthe types well known and described for: use in the production of cyaninedyes which contain in one of the or and 'Y positions to the quaternarynitrogen atom areactive. group selected from the class consisting ofthioether, selenoether and aminovinyl groups.

Process for theproduction of methine dyestufis which comprises reactinga compound of the general formula:

where D is the residue of a ring system selected from five-membered andsix-membered systems,

with an alkyl quaternary salt of a heterocycliccompound of any of thetypes known and described for use in the production of cyanine dyeswhich contain in one of the a and v positions to the quaternary nitrogenatom an w-alkylthio group.

6. Process for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

where D is the residue of a ring system selected from five-membered andsix-membered systems, with an alkyl quaternary-salt-of a heterocycliccompound of anyof' the types known and'describedfor use inthe productionof cyanine dyes which contain in oneof. the a and positions to thequaternary nitrogen atom an acetanilidovinyl group. a

'7. Process for the production of methine dyestuffs which comprisesreacting a compound of the generalformula:

I I D where R is selected from the class consisting of the hydrogen atomand hydrocarbon groups and D is the residue of a ring system selectedfrom five-membered and six-membered systems, with an alkyl, or aralkylquaternary salt of a heterocyclic nitrogen compound, of any of the typeswell known and described for use in the production of cyanine dyes whichcontain in one of the or and 1 positions to the quaternary nitrogen atoma reactive group selected from the class consisting of thioether,selenoether and aminovinyl groups, the reaction being efiected in thepresenceof a dehydrating solvent.

8. Process for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

where R is selected from the class consisting of the hydrogen atom andhydrocarbon groups and D is the residue of a ring system selected fromfive-membered and six-membered systems, with an alkyl or aralkylquaternary salt of a heterocyclic, nitrogen compound of any of the typeswell known and described for use in the production of cyanine dyes whichcontain in one of the or and Y positions to the quaternary nitrogen atoma reactive group selected from the class consisting of thioether;selenoether and aminovinyl groups, the reaction being effected in thepresence of acetic anhydride.

9. Process for the production of methine dyestuffs which comprisesreacting a compound of the generalformula:

where D is a chain of more than one and less than 4atoms selectedfromcarbon and nitrogen, at leastoneof these atoms being carbon; with analkyl quaternary salt of a heterocyclic compoundof any of the typesknown and described for use in the production of cyanine dyes whichcontain in one of the a and 7 positions to the quaternary nitrogen atoman w-alkylthio group, the reaction being efiected in the presence of adehydrating solvent.

10. Process for the production of methine dyestuffs. which, comprisesreacting a compound of the general formula:

IS o-somcoon where D is a chain of more than one and less than 4 atomsselected from carbon and nitrogen at least one of these atoms beingcarbon, with an alkyl quaternary salt of a heterocyclic c0m-' pounol ofany of the types known and described ,for use in the production ofcyanine dyes which contain in' one of the a and 'y positions to thequaternary nitrogen atom an acetanilidovinyl group, the reaction beingeffected in the presence of a dehydrating solvent.

where D is a chain of more than one and less than 4 atoms selected fromcarbon and nitrogen at least one of these atom's being carbon, with analkyl quaternary salt of a heterocyclic compound of any of the typesknown and described for use in the production of cyanine dyes whichcontain in one of the a and v positions to the quaternary nitrogen atoman w-alkylthio group, the reaction being effected in the presence ofacetic anhydride.

12. Process for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

D as 01110 0 OH where D is a chain of more than one and less than 4atoms selected from carbon and nitrogen at least one of these atomsbeing carbon, with an alkyl quaternary salt of a heterocyclic compoundof any of the types known and described for use in the production ofcyanine dyes which contain in one of the a and '7 positions to thequaternary nitrogen atom an acetanilidovinyl group, the reaction beingeffected in the presence of acetic anhydride.

13. Process for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

(JO-CH2 IN I where D is the residue of a benziminazole nucleus with analkyl or aralkyl quaternary salt of a heterocyclic nitrogen compound ofany of the types well known and described for use in the production ofcyanine dyes which contain in one of the or and '7 positions to thequaternary nitrogen atom a reactive group selected from the classconsisting of thioether, selenoether and aminovinyl groups,.the reactingbeing carried out in the presence of an acid binding agent.

14. Process for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

where D is the residue of a pyrimidyl nucleus with an alkyl or aralkylquaternary salt of a heterocyclic nitrogen compound of any of the typeswell known and described for use in the production of cyanine dyes whichcontain in one V 10. of the oz and '7 positions to the quaternarynitrogen atom a reactive group selected from the class consisting ofthioether, selenoether and aminovinyl groups, the reaction being carriedout in the presence of an acid binding agent.

15. Process for the production of methine dyestuffs which comprisesreacting a compound of the general formula:

I ,NH

/ D o-s cmc 0 0 R where R is selected from the class consisting of thehydrogen atom and hydrocarbon groups and D is the residue of a ringsystem selected from five-m'embered and siX-membered systems, with analkyl or aralkyl quaternary salt of a heterocyclic nitrogen compound ofany of the types well known and described for use in the production ofcyanine dyes which contain in one of the 0c and 7 positions to thequaternary nitrogen atom a reactive group selected from the classconsisting of thioether, selenoether and aminovinyl groups, the reactionbeing effected in the presence of acetic anhydride and an acid bindingagent.

16. A dyestuff of the general formula:

where D is the residue of a ring system selected from five-membered andsix-membered systems, R is an alkyl group, D1 is the residue of aheterooyclic nitrogen compound of the type commonly used in cyaninedyes, n is selected from the class consisting of nought, 1, 2 and 3, andm is selected from the class consisting of nought and one.

17. A dyestufi of the general formula:

where D is a chain of more than one and less than 4 atoms selected fromcarbon and nitrogen at least one of these atoms being carbon, R is analkyl group, D1 is the residue of a heterocyclic nitrogen compound ofthe type commonly used in cyanine dyes, n is selected from the classconsisting of nought, 1; 2 and 3, and m is selected from the classconsisting of nought and one.

18. A dyestufi of the general formula:

N D c 7 y \N where D is the residue of a ring system selected fromfive-membered and six-membered systems, R is an alkyl group, D1 is theresidue of a heterocyclic nitrogen nucleus selected from the classconsisting of the benzoxazole, benzthiazole and indolenine nuclei, n isselected from the class consisting of nought, l, 2 and 3, and m isselected from the class consisting of nought and one. JOHN DAVIDKENDALL. GEORGE FRANK DUFFTN.

(References on following page) REFERENCES CITED The following referencesare of recordyin the file ofvthis patent:

UNITED 'STATES PATENTS Number Name 'Date White et a1 July 18, 1939 WhiteNov. 25, 1941 Hamer et a1. June 15, 1943 Kendall Feb. 8, 1944 10 12Number Name Date 2342;546 Kendall Feb. 22,1944 "2,353,164 Kendall eta1.. July 11. 1944 OTHER REFERENCES Med. Journal, 1922, I 514-515)Chemical Abstracts 19:530 (Abstractof Proc.

Roy. Soc., London, 963 317333,'1924)

1. PROCESS FOR THE PRODUCTION OF METHINE DYESTUFFS WHICH COMPRISESREACTING A COMPOUND OF THE GENERAL FORMULA: